freebsd-nq/lib/libpthread/thread/thr_spec.c
Jeffrey Hsu f258836a24 Make pthread_getspecific() compliant with the final IEEE pthreads
specification:  return parameter passing changed.
1996-11-11 09:05:29 +00:00

238 lines
6.1 KiB
C

/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
/* Static variables: */
static struct pthread_key key_table[PTHREAD_KEYS_MAX];
int
pthread_key_create(pthread_key_t * key, void (*destructor) (void *))
{
for ((*key) = 0; (*key) < PTHREAD_KEYS_MAX; (*key)++) {
if (key_table[(*key)].count == 0) {
key_table[(*key)].count++;
key_table[(*key)].destructor = destructor;
return (0);
}
}
return (EAGAIN);
}
int
pthread_key_delete(pthread_key_t key)
{
int ret;
int status;
/* Block signals: */
_thread_kern_sig_block(&status);
if (key < PTHREAD_KEYS_MAX) {
switch (key_table[key].count) {
case 1:
key_table[key].destructor = NULL;
key_table[key].count = 0;
case 0:
ret = 0;
break;
default:
ret = EBUSY;
}
} else {
ret = EINVAL;
}
/* Unblock signals: */
_thread_kern_sig_unblock(status);
return (ret);
}
void
_thread_cleanupspecific(void)
{
void *data;
int key;
int itr;
int status;
/* Block signals: */
_thread_kern_sig_block(&status);
for (itr = 0; itr < PTHREAD_DESTRUCTOR_ITERATIONS; itr++) {
for (key = 0; key < PTHREAD_KEYS_MAX; key++) {
if (_thread_run->specific_data_count) {
if (_thread_run->specific_data[key]) {
data = (void *) _thread_run->specific_data[key];
_thread_run->specific_data[key] = NULL;
_thread_run->specific_data_count--;
if (key_table[key].destructor) {
key_table[key].destructor(data);
}
key_table[key].count--;
}
} else {
free(_thread_run->specific_data);
/* Unblock signals: */
_thread_kern_sig_unblock(status);
return;
}
}
}
free(_thread_run->specific_data);
/* Unblock signals: */
_thread_kern_sig_unblock(status);
}
static inline const void **
pthread_key_allocate_data(void)
{
const void **new_data;
if ((new_data = (const void **) malloc(sizeof(void *) * PTHREAD_KEYS_MAX)) != NULL) {
memset((void *) new_data, 0, sizeof(void *) * PTHREAD_KEYS_MAX);
}
return (new_data);
}
int
pthread_setspecific(pthread_key_t key, const void *value)
{
pthread_t pthread;
int ret = 0;
int status;
/* Block signals: */
_thread_kern_sig_block(&status);
/* Point to the running thread: */
pthread = _thread_run;
/*
* Enter a loop for signal handler threads to find the parent thread
* which has the specific data associated with it:
*/
while (pthread->parent_thread != NULL) {
/* Point to the parent thread: */
pthread = pthread->parent_thread;
}
if ((pthread->specific_data) || (pthread->specific_data = pthread_key_allocate_data())) {
if ((key < PTHREAD_KEYS_MAX) && (key_table)) {
if (key_table[key].count) {
if (pthread->specific_data[key] == NULL) {
if (value != NULL) {
pthread->specific_data_count++;
key_table[key].count++;
}
} else {
if (value == NULL) {
pthread->specific_data_count--;
key_table[key].count--;
}
}
pthread->specific_data[key] = value;
ret = 0;
} else {
ret = EINVAL;
}
} else {
ret = EINVAL;
}
} else {
ret = ENOMEM;
}
/* Unblock signals: */
_thread_kern_sig_unblock(status);
return (ret);
}
void *
pthread_getspecific(pthread_key_t key)
{
pthread_t pthread;
int status;
void *data;
/* Block signals: */
_thread_kern_sig_block(&status);
/* Point to the running thread: */
pthread = _thread_run;
/*
* Enter a loop for signal handler threads to find the parent thread
* which has the specific data associated with it:
*/
while (pthread->parent_thread != NULL) {
/* Point to the parent thread: */
pthread = pthread->parent_thread;
}
/* Check for errors: */
if (pthread == NULL) {
/* Return an invalid argument error: */
_thread_seterrno(_thread_run, EINVAL);
data = NULL;
}
/* Check if there is specific data: */
else if (pthread->specific_data != NULL && (key < PTHREAD_KEYS_MAX) && (key_table)) {
/* Check if this key has been used before: */
if (key_table[key].count) {
/* Return the value: */
data = (void *) pthread->specific_data[key];
} else {
/*
* This key has not been used before, so return NULL
* instead:
*/
data = NULL;
}
} else {
/* No specific data has been created, so just return NULL: */
data = NULL;
}
/* Unblock signals: */
_thread_kern_sig_unblock(status);
return (data);
}
#endif